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Revealed: Four different ways the Earth may look when the next supercontinent forms

Mattias Green, Hannah Sophia Davies and Joao C. Duarte writing for The Conversation

The outer layer of the Earth, the solid crust we walk on, is made up of broken pieces, much like the shell of a broken egg. These pieces, the tectonic plates, move around the planet at speeds of a few centimeters per year. Every so often they come together and combine into a supercontinent, which is a hundred million years before breaking up. The plates then disperse and move away from each other, until they eventually – after another 400-600 million years – come back together again.

The last supercontinent, Pangea, was formed around 310 million years ago, and started breaking up around 180 million years ago. It has been suggested that the next supercontinent will form in 200-250 million years, so we are currently about halfway through the scattered phase of the current supercontinent cycle. The question is how will the next supercontinent form, and why?

There are four fundamental scenarios for the formation of the next supercontinent: Novopangea, Pangea Ultima, Aurica and Amasia. How each form depends on different types of Pangea separated, and how the worlds continents are still moving today.

The breakup of Pangea led to the formation of the Atlantic Ocean, which is still opening and getting wider today. Consequently, the Pacific Ocean is closing and getting narrower. The Pacific is home to a ring of subduction zones along its edges (the "ring of fire"), where ocean floor is brought down, or subducted, under continental plates and into the Earth's interior. There, the old ocean floor is recycled and can go into volcanic plumes. The Atlantic, by contrast, has a large ocean ridge producing a new ocean plate, but is only home to two subduction zones: the Lesser Antilles Arc and the Scotia Arc between South America and Antarctica.

1. Novopangea

If we assume that the present day conditions persist, so that the Atlantic continues to open and the Pacific keeps closing, we have a supercontinent forms in the antipodes of Pangea. The Americas would have been collide with the northward drift of Antarctica, and then into the already collided Africa-Eurasia. The supercontinent that would have been named Novopangea, or Novopangaea.

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